A semi-precious stone that is also known as hyacinth. it is a lustrous
orange-yellow, orange-red, or yellow-brown type of zircon. Hyacinth
has a hardness of 7.5 and a specific gravity of 4.65. Sometimes, topaz
and grossular garnet of this color are also referred to as hyacinth
(this can be very confusing). Hyacinth is mined in Sri Lanka. Even
more confusing is the origin of the name, which comes from the Greek
hyakinthos, which refers to blue gemstone.
A semi-precious stone that ranges in color from green to white to
lilac to brown to almost black. Translucent jade is more highly
valued than opaque jade. Jade is often cabochon set; stones with
imperfections are often carved (the imperfections are simply carved
away). Two different minerals are known as jade: jadeite and nephrite.
Jadeite is the harder of the two; it is usually used in jewelry
production. Nephrite is slightly softer and is often veined; it
is used in carvings, for making beautiful bowls and vases. The Chinese
have prized jade for thousands of years and regarded it as having
medicinal properties when worn or ingested as a powder. Natural
jadeite is called Type A or Grade A jade (waxing or wax dipping
is allowed). Jadeite that had been bleached and then treated with
polymers (plastic) or waxes is called Type B or Grade B jade (it
is less durable than natural jade). Jadeite that had been dyed is
called Type C or Grade C jade (the color is less durable than that
of natural jade). Jadeite that has been both dyed and impregnated
with polymers is called Type B+C or Grade B+C.
Jade glass is translucent green glass that is designed to imitate
Jadeite is the harder of the two varieties of jade. Jadeite is harder
(compared to nephrite) and is usually used in jewelry production.
A Japanned finish in jewelry is when metal is finished with a lustrous,
black lacquer. The Maltese cross brooch above is by Weiss; it has
red paste stones and a Japanned finish.
A common, opaque, semi-precious stone that is found in many colors,
including white, brown, yellow, red, and green. Jasper is found
all over the world; it is often striped, speckled, and multi-colored.
Jasper has been used for intaglio carvings. Jasper is a type of
quartz belonging to the chalcedony family. It is often sealed with
petroleum products. Jasper is sometimes dyed to resemble lapis lazuli
and misleadingly called "Swiss lapis." Jasper has a hardness
of 6.5 to 7.0.
Jasperine refers to any type of banded jasper.
Jasperized wood (also called xyloid jasper) is petrified wood. It
is wood that has fossilized - all the original chemicals have been
replaced with minerals, making a stone-like replica of the original
Jasper ware (also spelled jasperware) is a type of porcelain (high-fired
white kaolin clay) made by the Wedgwood company. It is made into
molded cameos that are made into pins, pendants, and necklaces.
Jeanne was a mark used by Mark Dottenheim of NY, NY, for costume
jewelry, often figural. This mark was first used in October 1919.
The gold-plated Jeanne pin above depicts a bird's nest with tiny
A jelly belly is a piece of jewelry (usually a pin) that has a clear
lucite or glass center. The Trifari jelly belly fish pin above has
a faceted glass belly.
Georg Jensen (1866-1935) was a Danish silversmith, ceramic artist,
and sculptor. Jensen's modern-style silver jewelry is often adorned
with semi-precious stones and is avidly collected. Jensen's workshop
grew to have branches in Australia, New York, USA, and Toronto,
Jet (also known as gagate) is fossilized coal. It is a hard, lightweight
lustrous black stone that was used in mourning jewelry during the
Victorian era (especially after Queen Victoria's husband died in
1861 and she went into long period of mourning, greatly affecting
jewelry fashion). Jet is frequently cabochon cut. Most jet is from
Whitby, England; jet has been mined near Whitby (on the Yorkshire
coast of England) since prehistoric times. It is also found in Spain,
France, Germany, and Russia, but these other sources are said to
be inferior to the harder, more elastic Whitby jet. Jet has a hardness
of 2.5-4 (quite soft) and a specific gravity of 1.30-1.35 (it is
relatively lightweight). Jet leaves a brown streak. When burnt with
a red-hot needle, jet smells like coal. Black glass and plastics
are often used to imitate jet (glass is much heavier and harder
than jet) - jet is warm to the touch.
Jewelry (spelled jewellery in Britain) is articles of personal adornment,
like rings, necklaces, bracelets, cuff links, and pins. Jewelry
is made from metals (especially gold and silver), stones, glass,
plastic, and other materials.
J.J. is a registered trademark of the Jonette Jewelry Compant, East
Providence, R.I. This costume jewelry company was orignially called
the Providence Jewelry Co.; it was founded in 1935 by Abraham Lisker.
When Abraham Lisker's brother Nathan joined the company, the name
was changed to Lisker & Lisker Inc. Production was halted during
World War 2. After the war, the company was called the Jonette Jewelry
Company. Marked with the initials "J.J." their jewelry
is mostly figural and novelty pins, including Christmas pins. The
poodle above is a J.J. figural pin.
A jobber is a wholesale company that manufactures jewelry pieces
by the job for other companies. For example, De Lizza & Elster
was a jobber that supplied pieces for Weiss, Kramer, Kenneth J.
Lane, Hobe, Celebrity, Hattie Carnegie, Alice Caviness, Karu, and
Job's tears (Coix lacryma-jobi) is a wild tropical grass plant that
has very hard seeds. The white seeds are used as beads in jewelry.
The seeds are dried, dyed or painted, polished, drilled and then
strung into necklaces and bracelets.
Jomaz (or Mazer) is a costume jewelry mark used by the Joseph J.
Mazer company (founded in NY, NY, in 1927). Early pieces are marked
"Mazer Bros;" later pieces are marked JOMAZ or MAZER.
They went out of business in the 1970's. They make high-quality
jewelry like the gold-plated earring above with pearl and paste
Juliana jewelry is distinguished by many beautiful, brightly-colored
glass stones of different shapes and sizes (often including speckled
or "painted" stones), with very little metal showing in
the pieces. The well-made designs are very feminine, and often use
cluster settings. Stones were either prong-set (usually with four
prongs) or glued in. Juliana bracelets usually have five links and
a fold-over clasp (plus most have a safety chain with a spring ring).
Juliana pieces were marked with only a paper hang tag (a detachable
tag), so positive identification is not usually possible. Juliana
jewelry was produced from 1950 until the 1960s, and pieces are now
highly prized by collectors. Juliana pieces were manufactures by
the De Lizza & Elster company. A few other companies, including
"Gloria" (perhaps made by G. Fox and Co. of Hartford,
CT) and "Tara," sold pieces similar to Juliana pieces.
Juliana-style jewelry is unsigned costume jewelry that resembles
Juliana jewelry (see the previous entry)s, but the piece's origin
A jump ring is a circular metal ring with an opening.
It is used to attach two other rings or links, and is then soldered
or pressed shut.